GH Actions: Bump actions/checkout to version 3

Version 2 is based on Node.js 12 and is deprecated. Version 3 is based
on Node.js 16. There are some minor changes but none that affects
OpenSCAP. The action for 'CodeQL' already uses version 3.

Author: havardAasen

.github/workflows/build.yml

@@ -26,7 +26,7 @@ jobs:
     # Steps represent a sequence of tasks that will be executed as part of the job
     steps:
     # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
       with:
         submodules: recursive
 
@@ -61,7 +61,7 @@ jobs:
     - name: Install Deps
       run: dnf install -y cmake git dbus-devel GConf2-devel libacl-devel libblkid-devel libcap-devel libcurl-devel libgcrypt-devel libselinux-devel libxml2-devel libxslt-devel libattr-devel make openldap-devel pcre-devel perl-XML-Parser perl-XML-XPath perl-devel python3-devel rpm-devel swig bzip2-devel gcc-c++ libyaml-devel xmlsec1-devel xmlsec1-openssl-devel hostname bzip2 lua rpm-build which strace
     - name: Checkout
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
       with:
         submodules: recursive
     - name: Build
@@ -82,7 +82,7 @@ jobs:
     # Steps represent a sequence of tasks that will be executed as part of the job
     steps:
     # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
 
     # Runs a single command using the runners shell
     - name: Install Deps